Joseph datenport



part of this specification, and :to the letter-'sof reference marked thereon, of whichvdrawings- -J'o- SEPH DAAVENPO R12-'0F MASSI'LLON, OHIO I Letters .Patent No. 82,388, dated Septemer 22, 1868.

Q-9 i v 'IMPROVEMENT 1N encuen Banners.

uit: Srigetnle referat tu in ttettettirs' ttrnt mit making putt nf the sami.

l v I w V TO ALL WHQM IT MAY CONCERN: l i

Be it known that I, JOSuPH DAVENPORT, of Massillon, in. the county of Stark, and State of Ohio, have invented new and useful Improvements in Arch-Bridges audI do hereby declare that the following isa full,

clear, and exact description of my invention, reference being had to the accompanying drawinos, forming a Figure l is an elevation of a bridge-girder with my improvements.

shoesfwith lever-posts, rods, and tension-straps, 1n such a manner as that the arch of the bridge-girde'r shall be greatly strengthened against any vertical bending of said arch, at or near what may be termed the points ofrupture of 'said arch, whereby a'mnch stronger arch may be constructed from the same amount of material than has heretofore been made.

To enable others skilled in the art to make and-use my invention, I will proceed to describe its construcf tion and operation.V

The nature of my invention consists in' the peculiar arrangement of the brrdUe-girder, chords, and girder- The arch B, shown in drawings, is the'same 'as-the arch for which I was granted a `patent on the 244th day" of December, 1867, and which, as it is fullv described yin the, specification for that patent need not be further Y specified here, but I wish it understood that I do not limit the application of my improvements to this particular -form oi' arch.

l'he ends of the arch B rest in shoes G, which have the eyes z h formed at their sides.

The chords A are one in number to each girder, and are formed of continuous strips of'- plate-iron, set up edgewise, and parallel to each-other.

The bolts E E are of the form shown, being tiattened out at oneend, and are secured to the ends of the chords A by rivets or bolts c e, as shown. t The bolts E E pass through the eyes z t in the shoes G G, and by the'sides ofthe lever-posts KK through the washer-ironsF F,.where they are secured by nutsff,.as shown.

The posts or suspension-rods C C and diagonal braces D D are arranged and secured to the arch JB and chords A, as shown. Y t

The lever-posts K, s hown in detail in fig. 3, are composed of the side-pieces K K, of plate-iron, ofthe form shown, which are connected by the bolts or rivets l; k, and have secured, between said side-pieces K K, the.

blocks M M, having the pinsm cast thereon, and thecross-piece L with hole'l therein. These lever-posts K set against the rear part of t-he shoes GG, and have the washer-irons F F arranged so as to bind them in said The 'tensionstraps I Ihre formed ot' plate-iron, and .are secured at o ne end to the chords A,*by the` bolts z', as shown. They passup fro-m the chords, one on eachside of the arch, and are secured by a bolt or rivet, j, to the tension-bolt J. .This bolt J passes through the hole l in the cross-piece L in the leverpost K, and is -securcd by a nut, y, arranged as shown in fig. 3. l The lever-post rods N N are formed of hollow tubes, having one end flattened down, and secured tothe arch B by one-or more bolts n, while the other end abuts against the blocks M in the lever-posts K, the pins m on said blocks entering into the holiowof the tubesN, and hold them in position, as shown in g. The supports 0 arc'bolted to the arch B, and have holes c, through which passthe rods NN, thus giving a support to said rods. l

The floor ot the bridge is laid on cross-beams, which are arranged on the chords A, in an ordinary manner. A load being placed on the girdcr or bridge at a point, w, on the end of the same, hasa tendency to draw down the arch above it, and to cause the arch to rise at the'other end, above the point Y nerlthe other end,

sues

which rising is prevented* bythe rods N N, which press against the bloeit M in lever-'post K, which is prevented from turning by the tension-rods I. i 'A A load being placed at W,4 near the centre of the girder, has a tendency to draw down the centre of the arch, and cause a bending of the saine, at or near the points of rupture, above the points W and Y, which hending is prevented by the rods N N, as before shown, while the tension-straps I form, with the chords A, a

suspension-chain, which helps to carry the load at the centre, the p'osts K K being sustained against this strain by their lever-action over thelshoes G G, and against the washer-irons F F at the ends of the chord-bolts E E, and also by the rods'N N bearing on the arch IB. i

, Havngthus fully described my invention, what I clam as new, and desire to secure by Letters Pfatent, is- 1. The rods N N, when used in combination with the arch B and posts K K, substantially as and for the purpose specified. A y i 2 The supports O, when used in combination with tlierch B and rods N N, substantially as and for'th'e purpose specied.

3. The lever-posts K, when constructed4 o f Atheside-plates K K, bolts or rivets 7c 1:, blocks M M, and cross-- piece L, and used in combination with-the chord-bolt washer-iron F, the shoe.G,-.the tension-bolt J, with'strsps I I attached thereto and to the chords A., the rods N N, land the arch B, substantially as 'and for theypurpose herein specified. Y?

As evidence that I claim the foregoing, I have hereunto set my hand', in the presence of two witnesses, this 4u, day of May, A. D. 186s.

J. DAVENPORT.

Witnesses:

ED. L. BEEBOUT, J os ABBOTT. 

